Question 1
A square sheet of paper is folded horizontal (bottom to top). A hole is punched at the near the folded edge. When unfolded, what pattern will appear?
Step-by-Step Solution:
Step 1 - Initial Setup:
- Square paper folded horizontally from bottom to top
- Creates 2 overlapping layers
- Fold line is at the horizontal center
Step 2 - Fold Mechanics:
- Bottom half folds upward to cover top half
- Both layers are identical in size and shape
- Perfect alignment creates clean symmetry
Step 3 - Punch Location Analysis:
- Hole position: near the folded edge
- In folded state: appears close to the physical edge
- When unfolded: will appear near the center line
Step 4 - Unfolding Process:
- Carefully unfold along the horizontal crease
- Top layer hole remains at punch location
- Bottom layer hole mirrors across center line
- Result: Two holes close together near center horizontal line
Step 5 - Geometric Confirmation:
- Distance from center: equal for both holes
- Vertical alignment: both holes at same x-coordinate
- Pattern: symmetric about horizontal axis
Spatial Reasoning Technique:
Use coordinate geometry - if hole is at (x,y) on folded paper, unfolded positions are (x,y) and (x,100-y) for 100x100 paper.
Key Insight: The folded edge becomes the symmetry line when unfolded.